Most animal cell membranes have proteins that pump what ions out of the cell and potassium ions into the cell.
a. calcium
b. carbon
c. magnesium
d. sodium

Explain why ecosystem diversity results in species diversity in a healthy biosphere

This is a scaffolding of protein fibers that us sell keep it shape in a cell division and cell movement

Which of the following observation darwin shape his concept of descent with modification? a) species diversity declines farther from the equator. b) fewer species live on islands than on the nearest continents. c) birds live on islands located farther from the mainland than the bird's maximum nonstop flight distance. d) south american temperate plants are more similar to the tropical plants of south america than to the temperate plants of europe. e) earthquakes reshape life by causing mass extinctions.